LOANS AND ALLOWANCE FOR CREDIT LOSSES - Risk category of bank loans by year of origination (Details) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2023	Sep. 30, 2023
Origination year
2024		$ 28,067,000
2023		163,431,000
2022		348,286,000
2021		134,736,000
2020		86,768,000
Prior		228,753,000
Revolving Loans		25,584,000
Total Loans Receivable		1,015,625,000
Gross write-offs
2023		11,000
Total Loans Receivable		11,000
Commercial Real Estate Portfolio Segment
Origination year
Total Loans Receivable		917,432,000
Commercial Real Estate Portfolio Segment \| Commercial Business
Origination year
2024		6,242,000
2023		65,288,000
2022		90,402,000
2021		32,287,000
2020		18,649,000
Prior		14,727,000
Revolving Loans		14,446,000
Total Loans Receivable		242,041,000
Commercial Real Estate Portfolio Segment \| Commercial Real Estate
Origination year
2024		13,180,000
2023		64,231,000
2022		143,592,000
2021		91,021,000
2020		54,318,000
Prior		195,035,000
Total Loans Receivable		561,377,000
Commercial Real Estate Portfolio Segment \| Land
Origination year
2023		2,741,000
2022		1,404,000
2021		1,828,000
2020		115,000
Prior		470,000
Total Loans Receivable		6,558,000
Commercial Real Estate Portfolio Segment \| Multi-Family
Origination year
2024		526,000
2023		6,369,000
2022		32,402,000
2021		5,270,000
2020		9,174,000
Prior		2,930,000
Total Loans Receivable		56,671,000
Commercial Real Estate Portfolio Segment \| Real Estate Construction
Origination year
2024		7,837,000
2023		24,147,000
2022		18,801,000
Total Loans Receivable		50,785,000
Consumer
Origination year
Total Loans Receivable		98,193,000
Gross write-offs
Total Loans Receivable		11,000
Consumer \| Real estate one-to-four family
Origination year
2022		61,417,000
2021		4,223,000
2020		4,464,000
Prior		15,564,000
Revolving Loans		10,683,000
Total Loans Receivable		96,351,000
Consumer \| Other installment
Origination year
2024		282,000
2023		655,000
2022		268,000
2021		107,000
2020		48,000
Prior		27,000
Revolving Loans		455,000
Total Loans Receivable		1,842,000
Gross write-offs
2023		11,000
Total Loans Receivable	$ 11,000	11,000
Pass
Origination year
2024		27,827,000
2023		158,444,000
2022		344,195,000
2021		134,650,000
2020		86,110,000
Prior		208,269,000
Revolving Loans		19,959,000
Total Loans Receivable		979,454,000
Pass \| Commercial Real Estate Portfolio Segment \| Commercial Business
Origination year
2024		6,242,000
2023		64,468,000
2022		89,457,000
2021		32,201,000
2020		18,026,000
Prior		14,329,000
Revolving Loans		8,821,000
Total Loans Receivable		233,544,000
Pass \| Commercial Real Estate Portfolio Segment \| Commercial Real Estate
Origination year
2024		13,180,000
2023		60,424,000
2022		140,446,000
2021		91,021,000
2020		54,318,000
Prior		175,051,000
Total Loans Receivable		534,440,000
Pass \| Commercial Real Estate Portfolio Segment \| Land
Origination year
2023		2,381,000
2022		1,404,000
2021		1,828,000
2020		115,000
Prior		470,000
Total Loans Receivable		6,198,000
Pass \| Commercial Real Estate Portfolio Segment \| Multi-Family
Origination year
2024		526,000
2023		6,369,000
2022		32,402,000
2021		5,270,000
2020		9,139,000
Prior		2,868,000
Total Loans Receivable		56,574,000
Pass \| Commercial Real Estate Portfolio Segment \| Real Estate Construction
Origination year
2024		7,597,000
2023		24,147,000
2022		18,801,000
Total Loans Receivable		50,545,000
Pass \| Consumer \| Real estate one-to-four family
Origination year
2022		61,417,000
2021		4,223,000
2020		4,464,000
Prior		15,524,000
Revolving Loans		10,683,000
Total Loans Receivable		96,311,000
Pass \| Consumer \| Other installment
Origination year
2024		282,000
2023		655,000
2022		268,000
2021		107,000
2020		48,000
Prior		27,000
Revolving Loans		455,000
Total Loans Receivable		1,842,000
Special Mention
Origination year
2024		240,000
2023		4,987,000
2022		4,091,000
2021		86,000
2020		658,000
Prior		19,396,000
Revolving Loans		5,625,000
Total Loans Receivable		35,083,000
Special Mention \| Commercial Real Estate Portfolio Segment \| Commercial Business
Origination year
2023		820,000
2022		945,000
2021		86,000
2020		623,000
Prior		295,000
Revolving Loans		5,625,000
Total Loans Receivable		8,394,000
Special Mention \| Commercial Real Estate Portfolio Segment \| Commercial Real Estate
Origination year
2023		3,807,000
2022		3,146,000
Prior		19,069,000
Total Loans Receivable		26,022,000
Special Mention \| Commercial Real Estate Portfolio Segment \| Land
Origination year
2023		360,000
Total Loans Receivable		360,000
Special Mention \| Commercial Real Estate Portfolio Segment \| Multi-Family
Origination year
2020		35,000
Prior		32,000
Total Loans Receivable		67,000
Special Mention \| Commercial Real Estate Portfolio Segment \| Real Estate Construction
Origination year
2024		240,000
Total Loans Receivable		240,000
Substandard
Origination year
Prior		1,088,000
Total Loans Receivable		1,088,000
Substandard \| Commercial Real Estate Portfolio Segment \| Commercial Business
Origination year
Prior		103,000
Total Loans Receivable		103,000
Substandard \| Commercial Real Estate Portfolio Segment \| Commercial Real Estate
Origination year
Prior		915,000
Total Loans Receivable		915,000
Substandard \| Commercial Real Estate Portfolio Segment \| Multi-Family
Origination year
Prior		30,000
Total Loans Receivable		30,000
Substandard \| Consumer \| Real estate one-to-four family
Origination year
Prior		40,000
Total Loans Receivable		$ 40,000

Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-6

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
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-Section 45
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Amortized cost excluding accrued interest, of financing receivable originated more than five years prior to current fiscal year. Excludes net investment in lease.

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Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 326
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